Changing xattr of a temp file will trigger following assertion failed
and make ubifs turn into readonly filesystem:
  ubifs_assert_failed [ubifs]: UBIFS assert failed: host->i_nlink > 0,
  in fs/ubifs/journal.c:1801

Reproducer:
  1. fd = open(__O_TMPFILE)
  2. fsetxattr(fd, key, value2, XATTR_CREATE)
  3. fsetxattr(fd, key, value2, XATTR_REPLACE)

Fix this by removing assertion 'nlink > 0' for host inode.
Reported-by: Chengsong Ke <kechengsong@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

A detach hung is possible when a race occurs between the detach process
and the ubi background thread. The following sequences outline the race:

  ubi thread: if (list_empty(&ubi->works)...

  ubi detach: set_bit(KTHREAD_SHOULD_STOP, &kthread->flags)
              => by kthread_stop()
              wake_up_process()
              => ubi thread is still running, so 0 is returned

  ubi thread: set_current_state(TASK_INTERRUPTIBLE)
              schedule()
              => ubi thread will never be scheduled again

  ubi detach: wait_for_completion()
              => hung task!

To fix that, we need to check kthread_should_stop() after we set the
task state, so the ubi thread will either see the stop bit and exit or
the task state is reset to runnable such that it isn't scheduled out
indefinitely.
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>
Fixes: 801c135c ("UBI: Unsorted Block Images")
Reported-by: syzbot+853639d0cb16c31c7a14@syzkaller.appspotmail.com
Signed-off-by: Richard Weinberger <richard@nod.at>

Fix some potential memory leaks in error handling branches while
iterating dent entries. For example, function dbg_check_dir()
forgets to free pdent if it exists.
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>
Fixes: 1e51764a ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>

Fix some potential memory leaks in error handling branches while
iterating xattr entries. For example, function ubifs_tnc_remove_ino()
forgets to free pxent if it exists. Similar problems also exist in
ubifs_purge_xattrs(), ubifs_add_orphan() and ubifs_jnl_write_inode().
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>
Fixes: 1e51764a ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>

Pull USB/Thunderbolt fixes from Greg KH:
 "Here are some small USB and Thunderbolt driver fixes for 5.9-rc5.

  Nothing huge, just a number of bugfixes and new device ids for
  problems reported:

   - new USB serial driver ids

   - bug fixes for syzbot reported problems

   - typec driver fixes

   - thunderbolt driver fixes

   - revert of reported broken commit

  All of these have been in linux-next with no reported issues"

* tag 'usb-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: typec: intel_pmc_mux: Do not configure SBU and HSL Orientation in Alternate modes
  usb: typec: intel_pmc_mux: Do not configure Altmode HPD High
  usb: core: fix slab-out-of-bounds Read in read_descriptors
  Revert "usb: dwc3: meson-g12a: fix shared reset control use"
  usb: typec: ucsi: acpi: Check the _DEP dependencies
  usb: typec: intel_pmc_mux: Un-register the USB role switch
  usb: Fix out of sync data toggle if a configured device is reconfigured
  USB: serial: option: support dynamic Quectel USB compositions
  USB: serial: option: add support for SIM7070/SIM7080/SIM7090 modules
  thunderbolt: Use maximum USB3 link rate when reclaiming if link is not up
  thunderbolt: Disable ports that are not implemented
  USB: serial: ftdi_sio: add IDs for Xsens Mti USB converter

Pull staging/IIO driver fixes from Greg KH:
 "Here are a number of staging and IIO driver fixes for 5.9-rc5.

  The majority of these are IIO driver fixes, to resolve a timestamp
  issue that was recently found to affect a bunch of IIO drivers.

  The other fixes in here are:

   - small IIO driver fixes

   - greybus driver fix

   - counter driver fix (came in through the IIO fixes tree)

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (23 commits)
  iio: adc: mcp3422: fix locking on error path
  iio: adc: mcp3422: fix locking scope
  iio: adc: meson-saradc: Use the parent device to look up the calib data
  iio:adc:max1118 Fix alignment of timestamp and data leak issues
  iio:adc:ina2xx Fix timestamp alignment issue.
  iio:adc:ti-adc084s021 Fix alignment and data leak issues.
  iio:adc:ti-adc081c Fix alignment and data leak issues
  iio:magnetometer:ak8975 Fix alignment and data leak issues.
  iio:light:ltr501 Fix timestamp alignment issue.
  iio:light:max44000 Fix timestamp alignment and prevent data leak.
  iio:chemical:ccs811: Fix timestamp alignment and prevent data leak.
  iio:proximity:mb1232: Fix timestamp alignment and prevent data leak.
  iio:accel:mma7455: Fix timestamp alignment and prevent data leak.
  iio:accel:bmc150-accel: Fix timestamp alignment and prevent data leak.
  iio:accel:mma8452: Fix timestamp alignment and prevent data leak.
  iio: accel: kxsd9: Fix alignment of local buffer.
  iio: adc: rockchip_saradc: select IIO_TRIGGERED_BUFFER
  iio: adc: ti-ads1015: fix conversion when CONFIG_PM is not set
  counter: microchip-tcb-capture: check the correct variable
  iio: cros_ec: Set Gyroscope default frequency to 25Hz
  ...

Pull driver core fixes from Greg KH:
 "Here are some small driver core and debugfs fixes for 5.9-rc5

  Included in here are:

   - firmware loader memory leak fix

   - firmware loader testing fixes for non-EFI systems

   - device link locking fixes found by lockdep

   - kobject_del() bugfix that has been affecting some callers

   - debugfs minor fix

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  test_firmware: Test platform fw loading on non-EFI systems
  PM: <linux/device.h>: fix @em_pd kernel-doc warning
  kobject: Drop unneeded conditional in __kobject_del()
  driver core: Fix device_pm_lock() locking for device links
  MAINTAINERS: Add the security document to SECURITY CONTACT
  driver code: print symbolic error code
  debugfs: Fix module state check condition
  kobject: Restore old behaviour of kobject_del(NULL)
  firmware_loader: fix memory leak for paged buffer

Pull char / misc driver fixes from Greg KH:
 "Here are a number of small driver fixes for 5.9-rc5

  Included in here are:

   - habanalabs driver fixes

   - interconnect driver fixes

   - soundwire driver fixes

   - dyndbg fixes for reported issues, and then reverts to fix it all up
     to a sane state.

   - phy driver fixes

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Revert "dyndbg: accept query terms like file=bar and module=foo"
  Revert "dyndbg: fix problem parsing format="foo bar""
  scripts/tags.sh: exclude tools directory from tags generation
  video: fbdev: fix OOB read in vga_8planes_imageblit()
  dyndbg: fix problem parsing format="foo bar"
  dyndbg: refine export, rename to dynamic_debug_exec_queries()
  dyndbg: give %3u width in pr-format, cosmetic only
  interconnect: qcom: Fix small BW votes being truncated to zero
  soundwire: fix double free of dangling pointer
  interconnect: Show bandwidth for disabled paths as zero in debugfs
  habanalabs: fix report of RAZWI initiator coordinates
  habanalabs: prevent user buff overflow
  phy: omap-usb2-phy: disable PHY charger detect
  phy: qcom-qmp: Use correct values for ipq8074 PCIe Gen2 PHY init
  soundwire: bus: fix typo in comment on INTSTAT registers
  phy: qualcomm: fix return value check in qcom_ipq806x_usb_phy_probe()
  phy: qualcomm: fix platform_no_drv_owner.cocci warnings

Pull kvm fixes from Paolo Bonzini:
 "A bit on the bigger side, mostly due to me being on vacation, then
  busy, then on parental leave, but there's nothing worrisome.

  ARM:
   - Multiple stolen time fixes, with a new capability to match x86
   - Fix for hugetlbfs mappings when PUD and PMD are the same level
   - Fix for hugetlbfs mappings when PTE mappings are enforced (dirty
     logging, for example)
   - Fix tracing output of 64bit values

  x86:
   - nSVM state restore fixes
   - Async page fault fixes
   - Lots of small fixes everywhere"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (25 commits)
  KVM: emulator: more strict rsm checks.
  KVM: nSVM: more strict SMM checks when returning to nested guest
  SVM: nSVM: setup nested msr permission bitmap on nested state load
  SVM: nSVM: correctly restore GIF on vmexit from nesting after migration
  x86/kvm: don't forget to ACK async PF IRQ
  x86/kvm: properly use DEFINE_IDTENTRY_SYSVEC() macro
  KVM: VMX: Don't freeze guest when event delivery causes an APIC-access exit
  KVM: SVM: avoid emulation with stale next_rip
  KVM: x86: always allow writing '0' to MSR_KVM_ASYNC_PF_EN
  KVM: SVM: Periodically schedule when unregistering regions on destroy
  KVM: MIPS: Change the definition of kvm type
  kvm x86/mmu: use KVM_REQ_MMU_SYNC to sync when needed
  KVM: nVMX: Fix the update value of nested load IA32_PERF_GLOBAL_CTRL control
  KVM: fix memory leak in kvm_io_bus_unregister_dev()
  KVM: Check the allocation of pv cpu mask
  KVM: nVMX: Update VMCS02 when L2 PAE PDPTE updates detected
  KVM: arm64: Update page shift if stage 2 block mapping not supported
  KVM: arm64: Fix address truncation in traces
  KVM: arm64: Do not try to map PUDs when they are folded into PMD
  arm64/x86: KVM: Introduce steal-time cap
  ...

Pull OpenRISC fixes from Stafford Horne:
 "Fixes for compile issues pointed out by kbuild and one bug I found in
  initrd with the 5.9 patches"

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: Fix issue with get_user for 64-bit values
  openrisc: Fix cache API compile issue when not inlining
  openrisc: Reserve memblock for initrd

Pull seccomp fixes from Kees Cook:
 "This fixes a rare race condition in seccomp when using TSYNC and
  USER_NOTIF together where a memory allocation would not get freed
  (found by syzkaller, fixed by Tycho).

  Additionally updates Tycho's MAINTAINERS and .mailmap entries for his
  new address"

* tag 'seccomp-v5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  seccomp: don't leave dangling ->notif if file allocation fails
  mailmap, MAINTAINERS: move to tycho.pizza
  seccomp: don't leak memory when filter install races

Pull libnvdimm fix from Vishal Verma:
 "Fix detection of dax support for block devices.

  Previous fixes in this area, which only affected printing of debug
  messages, had an incorrect condition for detection of dax. This fix
  should finally do the right thing"

* tag 'libnvdimm-fix-v5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: fix detection of dax support for non-persistent memory block devices

Pull btrfs fixes from David Sterba:
 "A few more fixes:

   - regression fix for a crash after failed snapshot creation

   - one more lockep fix: use nofs allocation when allocating missing
     device

   - fix reloc tree leak on degraded mount

   - make some extent buffer alignment checks less strict to mount
     filesystems created by btrfs-convert"

* tag 'for-5.9-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix NULL pointer dereference after failure to create snapshot
  btrfs: free data reloc tree on failed mount
  btrfs: require only sector size alignment for parent eb bytenr
  btrfs: fix lockdep splat in add_missing_dev

Pull cifs fix from Steve French:
 "A fix for lookup on DFS link when cifsacl or modefromsid is used"

* tag '5.9-rc4-smb3-fix' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix DFS mount with cifsacl/modefromsid

Don't ignore return values in rsm_load_state_64/32 to avoid
loading invalid state from SMM state area if it was tampered with
by the guest.

This is primarly intended to avoid letting guest set bits in EFER
(like EFER.SVME when nesting is disabled) by manipulating SMM save area.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827171145.374620-8-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

* check that guest is 64 bit guest, otherwise the SVM related fields
  in the smm state area are not defined

* If the SMM area indicates that SMM interrupted a running guest,
  check that EFER.SVME which is also saved in this area is set, otherwise
  the guest might have tampered with SMM save area, and so indicate
  emulation failure which should triple fault the guest.

* Check that that guest CPUID supports SVM (due to the same issue as above)
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827162720.278690-4-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This code was missing and was forcing the L2 run with L1's msr
permission bitmap
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827162720.278690-3-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Currently code in svm_set_nested_state copies the current vmcb control
area to L1 control area (hsave->control), under assumption that
it mostly reflects the defaults that kvm choose, and later qemu
overrides  these defaults with L2 state using standard KVM interfaces,
like KVM_SET_REGS.

However nested GIF (which is AMD specific thing) is by default is true,
and it is copied to hsave area as such.

This alone is not a big deal since on VMexit, GIF is always set to false,
regardless of what it was on VM entry.  However in nested_svm_vmexit we
were first were setting GIF to false, but then we overwrite the control
fields with value from the hsave area.  (including the nested GIF field
itself if GIF virtualization is enabled).

Now on normal vm entry this is not a problem, since GIF is usually false
prior to normal vm entry, and this is the value that copied to hsave,
and then restored, but this is not always the case when the nested state
is loaded as explained above.

To fix this issue, move svm_set_gif after we restore the L1 control
state in nested_svm_vmexit, so that even with wrong GIF in the
saved L1 control area, we still clear GIF as the spec says.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827162720.278690-2-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

A build failure was raised by kbuild with the following error.

    drivers/android/binder.c: Assembler messages:
    drivers/android/binder.c:3861: Error: unrecognized keyword/register name `l.lwz ?ap,4(r24)'
    drivers/android/binder.c:3866: Error: unrecognized keyword/register name `l.addi ?ap,r0,0'

The issue is with 64-bit get_user() calls on openrisc.  I traced this to
a problem where in the internally in the get_user macros there is a cast
to long __gu_val this causes GCC to think the get_user call is 32-bit.
This binder code is really long and GCC allocates register r30, which
triggers the issue. The 64-bit get_user asm tries to get the 64-bit pair
register, which for r30 overflows the general register names and returns
the dummy register ?ap.

The fix here is to move the temporary variables into the asm macros.  We
use a 32-bit __gu_tmp for 32-bit and smaller macro and a 64-bit tmp in
the 64-bit macro.  The cast in the 64-bit macro has a trick of casting
through __typeof__((x)-(x)) which avoids the below warning.  This was
barrowed from riscv.

    arch/openrisc/include/asm/uaccess.h:240:8: warning: cast to pointer from integer of different size

I tested this in a small unit test to check reading between 64-bit and
32-bit pointers to 64-bit and 32-bit values in all combinations.  Also I
ran make C=1 to confirm no new sparse warnings came up.  It all looks
clean to me.

Link: https://lore.kernel.org/lkml/202008200453.ohnhqkjQ%25lkp@intel.com/Signed-off-by: Stafford Horne <shorne@gmail.com>
Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>

Merge commit 26d05b36 ("Merge branch 'kvm-async-pf-int' into HEAD")
tried to adapt the new interrupt based async PF mechanism to the newly
introduced IDTENTRY magic but unfortunately it missed the fact that
DEFINE_IDTENTRY_SYSVEC() doesn't call ack_APIC_irq() on its own and
all DEFINE_IDTENTRY_SYSVEC() users have to call it manually.

As the result all multi-CPU KVM guest hang on boot when
KVM_FEATURE_ASYNC_PF_INT is present. The breakage went unnoticed because no
KVM userspace (e.g. QEMU) currently set it (and thus async PF mechanism
is currently disabled) but we're about to change that.

Fixes: 26d05b36 ("Merge branch 'kvm-async-pf-int' into HEAD")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200908135350.355053-3-vkuznets@redhat.com>
Tested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

DEFINE_IDTENTRY_SYSVEC() already contains irqentry_enter()/
irqentry_exit().
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200908135350.355053-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

According to SDM 27.2.4, Event delivery causes an APIC-access VM exit.
Don't report internal error and freeze guest when event delivery causes
an APIC-access exit, it is handleable and the event will be re-injected
during the next vmentry.
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1597827327-25055-2-git-send-email-wanpengli@tencent.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

svm->next_rip is reset in svm_vcpu_run() only after calling
svm_exit_handlers_fastpath(), which will cause SVM's
skip_emulated_instruction() to write a stale RIP.

We can move svm_exit_handlers_fastpath towards the end of
svm_vcpu_run().  To align VMX with SVM, keep svm_complete_interrupts()
close as well.
Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Paul K. <kronenpj@kronenpj.dyndns.org>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
[Also move vmcb_mark_all_clean before any possible write to the VMCB.
 - Paolo]

Pull ceph fix from Ilya Dryomov:
 "Add missing capability checks in rbd, marked for stable"

* tag 'ceph-for-5.9-rc5' of git://github.com/ceph/ceph-client:
  rbd: require global CAP_SYS_ADMIN for mapping and unmapping

Pull i2c updates from Wolfram Sang:
 "Usual driver bugfixes for the I2C subsystem"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: algo: pca: Reapply i2c bus settings after reset
  i2c: npcm7xx: Fix timeout calculation
  misc: eeprom: at24: register nvmem only after eeprom is ready to use

Pull power management fixes from Rafael Wysocki:
 "These fix three pieces of documentation and add new CPU IDs to the
  Intel RAPL power capping driver.

  Specifics:

   - Add CPU IDs of the TigerLake Desktop, RocketLake and AlderLake
     chips to the Intel RAPL power capping driver (Zhang Rui).

   - Add the missing energy model performance domain item to the struct
     device kerneldoc comment (Randy Dunlap).

   - Fix the struct powercap_control_type kerneldoc comment to match the
     actual definition of that structure and add missing item to the
     struct powercap_zone_ops kerneldoc comment (Amit Kucheria)"

* tag 'pm-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  powercap: make documentation reflect code
  PM: <linux/device.h>: fix @em_pd kernel-doc warning
  powercap/intel_rapl: add support for AlderLake
  powercap/intel_rapl: add support for RocketLake
  powercap/intel_rapl: add support for TigerLake Desktop

Pull block fixes from Jens Axboe:

 - Fix a regression in bdev partition locking (Christoph)

 - NVMe pull request from Christoph:
      - cancel async events before freeing them (David Milburn)
      - revert a broken race fix (James Smart)
      - fix command processing during resets (Sagi Grimberg)

 - Fix a kyber crash with requeued flushes (Omar)

 - Fix __bio_try_merge_page() same_page error for no merging (Ritesh)

* tag 'block-5.9-2020-09-11' of git://git.kernel.dk/linux-block:
  block: Set same_page to false in __bio_try_merge_page if ret is false
  nvme-fabrics: allow to queue requests for live queues
  block: only call sched requeue_request() for scheduled requests
  nvme-tcp: cancel async events before freeing event struct
  nvme-rdma: cancel async events before freeing event struct
  nvme-fc: cancel async events before freeing event struct
  nvme: Revert: Fix controller creation races with teardown flow
  block: restore a specific error code in bdev_del_partition

Pull spi fixes from Mark Brown:
 "There's some driver specific fixes here plus one core fix for memory
  leaks that could be triggered by a potential race condition when
  cleaning up after we have split transfers to fit into what the
  controller can support"

* tag 'spi-fix-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: stm32: fix pm_runtime_get_sync() error checking
  spi: Fix memory leak on splited transfers
  spi: spi-cadence-quadspi: Fix mapping of buffers for DMA reads
  spi: stm32: Rate-limit the 'Communication suspended' message
  spi: spi-loopback-test: Fix out-of-bounds read
  spi: spi-cadence-quadspi: Populate get_name() interface
  MAINTAINERS: add myself as maintainer for spi-fsl-dspi driver

Merge tag 'regulator-fix-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

Pull regulator fixes from Mark Brown:
 "The biggest set of fixes here is those from Michał Mirosław fixing
  some locking issues with coupled regulators that are triggered in
  cases where a coupled regulator is used by a device involved in
  fs_reclaim like eMMC storage.

  These are relatively serious for the affected systems, though the
  circumstances where they trigger are very rare"

* tag 'regulator-fix-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: pwm: Fix machine constraints application
  regulator: core: Fix slab-out-of-bounds in regulator_unlock_recursive()
  regulator: remove superfluous lock in regulator_resolve_coupling()
  regulator: cleanup regulator_ena_gpio_free()
  regulator: plug of_node leak in regulator_register()'s error path
  regulator: push allocation in set_consumer_device_supply() out of lock
  regulator: push allocations in create_regulator() outside of lock
  regulator: push allocation in regulator_ena_gpio_request() out of lock
  regulator: push allocation in regulator_init_coupling() outside of lock
  regulator: fix spelling mistake "Cant" -> "Can't"
  regulator: cros-ec-regulator: Add NULL test for devm_kmemdup call

Even without in-kernel LAPIC we should allow writing '0' to
MSR_KVM_ASYNC_PF_EN as we're not enabling the mechanism. In
particular, QEMU with 'kernel-irqchip=off' fails to start
a guest with

qemu-system-x86_64: error: failed to set MSR 0x4b564d02 to 0x0

Fixes: 9d3c447c ("KVM: X86: Fix async pf caused null-ptr-deref")
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200911093147.484565-1-vkuznets@redhat.com>
[Actually commit the version proposed by Sean Christopherson. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

There may be many encrypted regions that need to be unregistered when a
SEV VM is destroyed.  This can lead to soft lockups.  For example, on a
host running 4.15:

watchdog: BUG: soft lockup - CPU#206 stuck for 11s! [t_virtual_machi:194348]
CPU: 206 PID: 194348 Comm: t_virtual_machi
RIP: 0010:free_unref_page_list+0x105/0x170
...
Call Trace:
 [<0>] release_pages+0x159/0x3d0
 [<0>] sev_unpin_memory+0x2c/0x50 [kvm_amd]
 [<0>] __unregister_enc_region_locked+0x2f/0x70 [kvm_amd]
 [<0>] svm_vm_destroy+0xa9/0x200 [kvm_amd]
 [<0>] kvm_arch_destroy_vm+0x47/0x200
 [<0>] kvm_put_kvm+0x1a8/0x2f0
 [<0>] kvm_vm_release+0x25/0x30
 [<0>] do_exit+0x335/0xc10
 [<0>] do_group_exit+0x3f/0xa0
 [<0>] get_signal+0x1bc/0x670
 [<0>] do_signal+0x31/0x130

Although the CLFLUSH is no longer issued on every encrypted region to be
unregistered, there are no other changes that can prevent soft lockups for
very large SEV VMs in the latest kernel.

Periodically schedule if necessary.  This still holds kvm->lock across the
resched, but since this only happens when the VM is destroyed this is
assumed to be acceptable.
Signed-off-by: David Rientjes <rientjes@google.com>
Message-Id: <alpine.DEB.2.23.453.2008251255240.2987727@chino.kir.corp.google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

MIPS defines two kvm types:

 #define KVM_VM_MIPS_TE          0
 #define KVM_VM_MIPS_VZ          1

In Documentation/virt/kvm/api.rst it is said that "You probably want to
use 0 as machine type", which implies that type 0 be the "automatic" or
"default" type. And, in user-space libvirt use the null-machine (with
type 0) to detect the kvm capability, which returns "KVM not supported"
on a VZ platform.

I try to fix it in QEMU but it is ugly:
https://lists.nongnu.org/archive/html/qemu-devel/2020-08/msg05629.html

And Thomas Huth suggests me to change the definition of kvm type:
https://lists.nongnu.org/archive/html/qemu-devel/2020-09/msg03281.html

So I define like this:

 #define KVM_VM_MIPS_AUTO        0
 #define KVM_VM_MIPS_VZ          1
 #define KVM_VM_MIPS_TE          2

Since VZ and TE cannot co-exists, using type 0 on a TE platform will
still return success (so old user-space tools have no problems on new
kernels); the advantage is that using type 0 on a VZ platform will not
return failure. So, the only problem is "new user-space tools use type
2 on old kernels", but if we treat this as a kernel bug, we can backport
this patch to old stable kernels.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Message-Id: <1599734031-28746-1-git-send-email-chenhc@lemote.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Pull MMC fixes from Ulf Hansson:
 "MMC core:
   - sdio: Restore ~20% performance drop for SDHCI drivers, by using
     mmc_pre_req() and mmc_post_req() for SDIO requests.

  MMC host:
   - sdhci-of-esdhc: Fix support for erratum eSDHC7
   - mmc_spi: Allow the driver to be built when CONFIG_HAS_DMA is unset
   - sdhci-msm: Use retries to fix tuning
   - sdhci-acpi: Fix resume for eMMC HS400 mode"

* tag 'mmc-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdio: Use mmc_pre_req() / mmc_post_req()
  mmc: sdhci-of-esdhc: Don't walk device-tree on every interrupt
  mmc: mmc_spi: Allow the driver to be built when CONFIG_HAS_DMA is unset
  mmc: sdhci-msm: Add retries when all tuning phases are found valid
  mmc: sdhci-acpi: Clear amd_sdhci_host on reset

When kvm_mmu_get_page() gets a page with unsynced children, the spt
pagetable is unsynchronized with the guest pagetable. But the
guest might not issue a "flush" operation on it when the pagetable
entry is changed from zero or other cases. The hypervisor has the
responsibility to synchronize the pagetables.

KVM behaved as above for many years, But commit 8c8560b8
("KVM: x86/mmu: Use KVM_REQ_TLB_FLUSH_CURRENT for MMU specific flushes")
inadvertently included a line of code to change it without giving any
reason in the changelog. It is clear that the commit's intention was to
change KVM_REQ_TLB_FLUSH -> KVM_REQ_TLB_FLUSH_CURRENT, so we don't
needlessly flush other contexts; however, one of the hunks changed
a nearby KVM_REQ_MMU_SYNC instead.  This patch changes it back.

Link: https://lore.kernel.org/lkml/20200320212833.3507-26-sean.j.christopherson@intel.com/
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20200902135421.31158-1-jiangshanlai@gmail.com>
fixes: 8c8560b8 ("KVM: x86/mmu: Use KVM_REQ_TLB_FLUSH_CURRENT for MMU specific flushes")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

A minor fix for the update of VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL field
in exit_ctls_high.

Fixes: 03a8871a ("KVM: nVMX: Expose load IA32_PERF_GLOBAL_CTRL
VM-{Entry,Exit} control")
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20200828085622.8365-5-chenyi.qiang@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

when kmalloc() fails in kvm_io_bus_unregister_dev(), before removing
the bus, we should iterate over all other devices linked to it and call
kvm_iodevice_destructor() for them

Fixes: 90db1043 ("KVM: kvm_io_bus_unregister_dev() should never fail")
Cc: stable@vger.kernel.org
Reported-and-tested-by: syzbot+f196caa45793d6374707@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=f196caa45793d6374707Signed-off-by: Rustam Kovhaev <rkovhaev@gmail.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200907185535.233114-1-rkovhaev@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

check the allocation of per-cpu __pv_cpu_mask. Initialize ops only when
successful.
Signed-off-by: Haiwei Li <lihaiwei@tencent.com>
Message-Id: <d59f05df-e6d3-3d31-a036-cc25a2b2f33f@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

When L2 uses PAE, L0 intercepts of L2 writes to CR0/CR3/CR4 call
load_pdptrs to read the possibly updated PDPTEs from the guest
physical address referenced by CR3.  It loads them into
vcpu->arch.walk_mmu->pdptrs and sets VCPU_EXREG_PDPTR in
vcpu->arch.regs_dirty.

At the subsequent assumed reentry into L2, the mmu will call
vmx_load_mmu_pgd which calls ept_load_pdptrs. ept_load_pdptrs sees
VCPU_EXREG_PDPTR set in vcpu->arch.regs_dirty and loads
VMCS02.GUEST_PDPTRn from vcpu->arch.walk_mmu->pdptrs[]. This all works
if the L2 CRn write intercept always resumes L2.

The resume path calls vmx_check_nested_events which checks for
exceptions, MTF, and expired VMX preemption timers. If
vmx_check_nested_events finds any of these conditions pending it will
reflect the corresponding exit into L1. Live migration at this point
would also cause a missed immediate reentry into L2.

After L1 exits, vmx_vcpu_run calls vmx_register_cache_reset which
clears VCPU_EXREG_PDPTR in vcpu->arch.regs_dirty.  When L2 next
resumes, ept_load_pdptrs finds VCPU_EXREG_PDPTR clear in
vcpu->arch.regs_dirty and does not load VMCS02.GUEST_PDPTRn from
vcpu->arch.walk_mmu->pdptrs[]. prepare_vmcs02 will then load
VMCS02.GUEST_PDPTRn from vmcs12->pdptr0/1/2/3 which contain the stale
values stored at last L2 exit. A repro of this bug showed L2 entering
triple fault immediately due to the bad VMCS02.GUEST_PDPTRn values.

When L2 is in PAE paging mode add a call to ept_load_pdptrs before
leaving L2. This will update VMCS02.GUEST_PDPTRn if they are dirty in
vcpu->arch.walk_mmu->pdptrs[].

Tested:
kvm-unit-tests with new directed test: vmx_mtf_pdpte_test.
Verified that test fails without the fix.

Also ran Google internal VMM with an Ubuntu 16.04 4.4.0-83 guest running a
custom hypervisor with a 32-bit Windows XP L2 guest using PAE. Prior to fix
would repro readily. Ran 14 simultaneous L2s for 140 iterations with no
failures.
Signed-off-by: Peter Shier <pshier@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Message-Id: <20200820230545.2411347-1-pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Merge tag 'kvmarm-fixes-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for Linux 5.9, take #1

- Multiple stolen time fixes, with a new capability to match x86
- Fix for hugetlbfs mappings when PUD and PMD are the same level
- Fix for hugetlbfs mappings when PTE mappings are enforced
  (dirty logging, for example)
- Fix tracing output of 64bit values

Pull drm fixes from Dave Airlie:
 "Regular fixes, not much a major amount. One thing though is Laurent
  fixed some Kconfig issues, and I'm carrying the rapidio kconfig change
  so the drm one for xlnx driver works. He hadn't got a response from
  rapidio maintainers.

  Otherwise, virtio, sun4i, tve200, ingenic have some fixes, one audio
  fix for i915 and a core docs fix.

  kconfig:
   - rapidio/xlnx kconfig fix

  core:
   - Documentation fix

  i915:
   - audio regression fix

  virtio:
   - Fix double free in virtio
   - Fix virtio unblank
   - Remove output->enabled from virtio, as it should use crtc_state

  sun4i:
   - Add missing put_device in sun4i, and other fixes
   - Handle sun4i alpha on lowest plane correctly

  tv200:
   - Fix tve200 enable/disable

  ingenic
   - Small ingenic fixes"

* tag 'drm-fixes-2020-09-11' of git://anongit.freedesktop.org/drm/drm:
  drm/i915: fix regression leading to display audio probe failure on GLK
  drm: xlnx: dpsub: Fix DMADEVICES Kconfig dependency
  rapidio: Replace 'select' DMAENGINES 'with depends on'
  drm/virtio: drop virtio_gpu_output->enabled
  drm/sun4i: backend: Disable alpha on the lowest plane on the A20
  drm/sun4i: backend: Support alpha property on lowest plane
  drm/sun4i: Fix DE2 YVU handling
  drm/tve200: Stabilize enable/disable
  dma-buf: fence-chain: Document missing dma_fence_chain_init() parameter in kerneldoc
  dma-buf: Fix kerneldoc of dma_buf_set_name()
  drm/virtio: fix unblank
  Documentation: fix dma-buf.rst underline length warning
  drm/sun4i: Fix dsi dcs long write function
  drm/ingenic: Fix driver not probing when IPU port is missing
  drm/ingenic: Fix leak of device_node pointer
  drm/sun4i: add missing put_device() call in sun8i_r40_tcon_tv_set_mux()
  drm/virtio: Revert "drm/virtio: Call the right shmem helpers"